Dynamo-electric machine filter



Oct. 13, 1936. L, A, K CH, JR 2,057,196

DYNAMO-ELECTRIC MACHINE FILTER Filed Dec. 23, 1952 VII/I glwuzntox LOUISA. KOCH JR.

firflu Patented Oct. 13, 1936 PATENT OFFICE DYNAMO-ELECTRIC MACHINEFILTER Louis A. Koch,

Jr., Louisville, Ky.

Application December 23, 1932, Serial No. 648,523

4 Claims.

This invention relates to replaceable air filter structure particularlyapplicable to dynamo-electric machines, such as used on automotivevehicles.

The principal object of this invention is the production of an airfilter structure that will occupy unused limited space adjacent anautomotive dynamo and effectively remove foreign matter from air as itis forced through a wall of the dynamo to the interior for removingdestructive heat incident to electric overloads that are imposed on thewindings, commutator and brushes and has a direct application to theprinciples of generator cooling set forth in applicants copendingapplication, Ser. No. 641,481.

A further object is the accomplishment of the above stated object withpositive and inexpensive equipment and of a type that can be readilyunderstood and sufiiciently accessible and easily manipulated to insurethe desideratum.

The means employed according to this invention constitutes structurewherein the special air filter or cleaning equipment can be built intothe unit during its manufacture or it can be subsequently lodgedadjacent, or to same, and organized to function as if it has beenoriginally built into the apparatus.

It is at once apparent that the apparatus provided by this invention formaintaining the generator at full normal capacity would enable a givensize of generator unit to care for a greater volt-ampere output than ifthe unit were not so equipped.

Other objects and advantages of the structure are hereinafter set forthin detail and will be apparent to persons skilled in the art to whichthe invention relates and to these advantages in so far as they arepatentably novel I will claim, the same as hereinafter set forth.

apertured face plate shown in cross section in Fig. 1, also in Fig. 6.

Figs. 3 and 3A represent respectively the top and elevational views ofthe air filter strap or cover.

Fig. 4 is a perspective view of the air filter medium on an enlargedscale.

Fig. 5 is an elevation of the end view of the drive end housing memberof the generator to disclose the part as prepared for admitting air,dotted lines indicate the filter location.

Fig. 6 is a cross sectional view of Fig. 5 along line 6, 6, togetherwith the filter strap of Fig. 3, and the filter face plate of Fig. 2added and forming a housing or frame for the filter medium shown in Fig.4.

Fig. '7 is a plan view of a section of the air filter strap, while Fig.8 is a cross section of Fig. 7 along the line 8, 8.

Fig. 9 is a side elevational View of a modified structure of an airfilter strap or cover.

Fig. 10 is a cross sectional view of an end plate of the generator towhich is attached the air filter strap Fig. 9, with an air filter mediumlodged therein.

Structure Numeral it indicates an electric generator, I l a radiatorcooling fan, both of which are attached to and operated by internalcombustion engine l2 by belt l3 in the conventional way, there beingpulley I2A attached to the main crank shaft of the engine, pulley l IAfixed on the shaft that operates the radiator fan and pulley IBA fixedon to shaft [4 of the generator mounted in bearings l5, l6. This shaft[4 carries the armature on which are mounted the commutator, laminae andwindings after the conventional practice.

Bearing I5 is a part of end housing H which is altered to provideopenings [8 to admit air currents, indicated by arrows, created by fanblades IOB disposed between pulley [0A and the end housing, also byauxiliary fan I9 fixed to shaft [4 and disposed between said housing andthe windings.

Between fan blades IOB and housing ll there is located a special type ofair filter medium 20, disposed in a very special type of housing ormatrix consisting of face plate 2| secured to end housing I! by screws22 and a strap member 23 which surrounds the face plate and is lodged onsame as well as on the end plate ll. It is essential to keep filter padclean, therefore easy means are provided by employing a flimsy amorphousmedium which is incompetent, by reason of its structure, to take andkeep a sufficiently definite form and still function as a filter underthe encountered conditions. This medium is easy to remove, clean andreturn to a frame or matrix provided on the generator, the mereinsertion of which results in an effective filter.

It will be noted that strap 23 is of sufficient width to extend over thearea in which fan blades HlB rotate. This strap serves not only toprotect the fan from injury, but to assist in directing air currentsthrough openings ZIA and I8 which communicate with the interior of thegenerator, where the air currents are again accelerated by interior fanl9. Both fans work together toexpel air from openings 24 disposed at theother end of the generator, preferably in commutator strap 25. Whilethese fans are of the same general structure, the blades of fan l9 havean increased pitch according to the velocity of the air, as a means ofderiving the full benefit of both groups of blades which would not bethe case if both sets of blades had the same pitch owing to the factthat when the air reaches blades I9 it is already well accelerated.

Operation Inasmuch as these generators are disposed under the hoods ofautomobiles, it was found desirable to provide means for an easy andquick removal of the filter medium that becomes laden with foreignmatter, and to be able to instantly replace it with a fresh medium.Therefore the filter strap 23 is provided with a latch 23A, which isarranged to engage the eye 23B, when in place, at the other end of thestrap, and thereby secure same in a permanent way and confine themedium. Therefore the latch can be sprung, strap removed, used mediaremoved, a media replaced and strap returned, all in a very brief periodof time.

It will be noted that this filter normally is in a bar form shown in.Fig. 4 and that it is radially applied to the circular filter housingand forced to take up a generally circular form. To assist in locatingthis strap, lip 26, which is pressed or bent out of the strap 23 asillustrated in Figs. 7 and 8, is provided and so located that it willengage the inner surface of face plate 2! and thereby prevent the strapfrom displacement.

M o difi cation The strap 30 shown in Fig. 9 is made with dependingwalls 3|, 32, the object being to suitably attach filter media to thestrap and to further increase the facilities with which the filter canbe changed. It will be noted that depending wall is arranged to fit intogroove 33 of end housing I! Which serves to lock and secure the filter.

Scope With the object of this invention and the structure of the meansfor accomplishing same having been disclosed, many furthermodifications, substitutions or eliminations can be indulged and themeans for accomplishing same can be varied without departing from thespirit of this invention, therefore I do not wish to be limited to thespecific forms shown and described, and desire to be limited only by theappended claims.

I claim:

1. In a dynamo-electric machine having an enclosing housing with anoutlet at one end and an inlet at the other end, a shaft mounted inbearings carried by said ends, a fan carried by said shaft andcooperating with the inlet to force air through said housing via theinlet and the outlet, aremovable filter medium associated with saidinlet, a fixed frame for said medium, and a detachable band encompassingsaid frame and extended to embrace at least a portion of said fan.

2. In a dynamo-electric machine having an enclosing housing with anoutlet at one end and an inlet at the other end, a shaft mounted inbearings carried by said ends, a fan carried by said shaft andcooperating with the inlet to force air through said housing via theinlet and the outlet, and a removable filter medium associated with saidinlet, a fixed frame for said medium, said frame being disposed betweenthe fan and the inlet and a detachable band encompassing said frame andlongitudinally extended to embrace at least a portion of said fan.

3. In a dynamo-electric machine having an enclosing housing with anoutlet at one end and an inlet at the other end, a shaft mounted inbearings carried by said ends, a fan carried by said shaft andcooperating with the inlet to force air through said housing via theinlet and the outlet, a removable filter medium associated with saidinlet, a fixed frame for said medium, said frame comprising a pair ofdiscal juxtapositioned members and a detachable band encompassing saidframe.

4. In a dynamo-electric machine having an enclosing housing with anoutlet at one end and an inlet at the other end, a shaft mounted inbearings carried by said ends, a fan carried by said shaft andcooperating with the inlet to force air through said housing via theinlet and the outlet, a removable filter medium associated with saidinlet, a fixed frame for said medium, said frame comprising a pair ofdiscal juxtapositioned members and a. detachable band encompassing saidframe and extended toembrace at least a portion of said fan.

LOUIS A. KOCH, JR.

